This application claims priority to Japanese Patent Application No. 2000-264703 filed on Aug. 31, 2000 in Japan. The contents of the aforementioned application are hereby incorporated by reference.
The present invention relates to a humidifier to isolate moisture in a gas with hollow fiber membranes.
As humidifier which exchanges moisture with this species of hollow fiber membrane, this applicant is proposing a humidifier (Japanese Laid-open Patent Publication No. 2001-202977).
FIGS. 8 and 9 are indicating this humidifier 50, a plurality of hollow fiber membrane modules 52 are supported in a pair of head block 51. Each hollow fiber membrane module 52 is comprised of the structure that the bunch of water permeable hollow fiber membrane 54 (herein after called as hollow fiber membrane) is axially inserted into a cylindrical housing 53 in which the both ends are opened, and both ends of the bunch of hollow fiber membrane 54 are stuck through a resin in the inner face of both ends of a cylindrical housing 53, and what is more, a plurality of peripheral aperture 55 which becomes inlet and outlet port for gas is peripherally established at interval on the both end of peripheral portion of housing 53 of each hollow membrane module 52.
A pair of head block 51 are supported by inserting said hollow fiber membrane module 52 into between each supporting hole 56 opening in the inner face of head block 51. Therefore, when a pair of head block 51 is connected together, a plurality of peripheral apertures 55 established in both ends of each peripheral housing 53 are consecutively pierced into the expanded cylindrical first chamber 58 in the center portion of supporting hole 56 of each head block 51, apertures in both end of each hollow fiber membrane 54 are consecutively pierced into second chamber 59 which is sectioned inside of each head block 51.
Each first chamber 58 and second chamber 59 is consecutively pierced into the first passage 60 and the second passage 61 respectively through the first common passage 62 and the second common passage 63 sectioned in each head block 51 respectively. This causes moisture in humid gas to move to peripheral surface of each hollow membrane 54 due to capillary phenomenon (capillary condensation phenomenon) when high humidity gas is supplied into the second passage 61 while low humidity gas (including a dry gas) is supplied into the first passage 60, consequently, this moisture humidifies low humid gas circulating through the first passage 60.
In this way, said humidifier 50 sections the first passage 60, the second passage 61, the first common passage 62, the second common passage 63, the first chamber 58, the second chamber 59 and a supporting hole 56 in a pair of head block 51, and then the first passage 60 and the second passage 61 are communicated with the housing 53 of each hollow fiber membrane module 52 and each hollow fiber membrane 54 through the first chamber 58 and the second chamber 59 respectively, however, end mill machining or drill machining is indispensable to form said first passage 60 and the second passage 61, etc in one head block 51, what is more, boring machining by boring lathe is indispensable to form the first chamber 58 and the second chamber 59. Therefore, these cause complication and increasing man-hour, consequently it is not provided inexpensively.
Furthermore, said humidifier 50 is adopting the structure to communicate the first passage 60 with housing 53 of hollow fiber membrane module 52 through the first chamber 58 and a plurality of peripheral aperture 55, but even though a route section is invariable, a pressure loss is occurred in response to the distance from the joint portion of the first passage 60 and the first common passage 62 to each first chamber 58 and the circumferential distance from the first chamber 58 to each peripheral aperture 55, which causes a flow rate disproportion, consequently, moisture exchanging rate is variable in every each hollow fiber module 52.
For the reason of this, pressure loss must be decreased by enlarging route section of the first passage 60,the second passage 61, the first common passage 62, the second common passage 63, the first chamber 58 and the second chamber 59, but end mill machining or drill machining and boring machining to form holes for an object of rotation can not help for enlarging a diameter of establishing hole, consequently, these can not contribute to downsizing and lightening a head block 51.
What is more, In said humidifier 50, connecting the second passage 61 to the second common passage 63 communicating with between each second chamber 59 for communication allows the gas for moisture exchanging to circulate in each hollow fiber membrane 54 of each hollow fiber membrane module 52, however, when assuming a pressure loss at the passage based on the joint point of the second passage 60, the flow rate of each hollow fiber membrane 54 is different respectively.
For the reason of this, a diameter of establishing hole to form the second passage 61, the second passage 63 and the second chamber 59 can not help for expanding to enlarge the head block 51 to cope with a pressure loss by end mill machining or drill machining and boring machining.
Besides, this applicant is proposing another humidifier in (Japanese Laid-open Patent Publication No. 2001-202977). This humidifier is supporting a plurality of hollow fiber membrane modules on a pair of bulkheads positioned at intervals each other to comprise a head block which sections said first passage and the second passage with the bulkhead at the left, right, up and down. However, this is not sufficient to solve said object.
The primary object of the present invention is to make simple structure, easy manufacturing and assembling. Furthermore, the second object of the present invention is to practically improve the moisture-exchanging rate of a humidifier.
The present invention is proposed to attain the primary object, and is to provide a humidifier comprised of a cylindrical housing in which a plurality of hollow fiber membranes inserted therein and a plurality of peripheral apertures disposed thereon are established and both ends of the housing are opened, a first plate having a dent portion on a part of the surface, and a second plate having a dent portion on a part of the surface, in addition, a plurality of plates including said first and second plates being overlapped whereby the dent portion of said first plate forms a first passage and the dent portion of said second plate forms a second passage, and said first passage being connected to said peripheral apertures and said second passage being connected to both ends of said open ends of the housing whereby moisture-exchange between a first fluid passing through said first passage to be introduced into the outside of said hollow fiber membranes and a second fluid passing through said second passage to be introduced into the inside of said hollow fiber membranes. That is to say, when said first passage and second passage are sectioned by denting a contact surface of a plurality of plate polymerized each other, these two passage can be formed under the condition to have made open the first passage and the second passage out.
This allows the first passage and the second passage to be formed and assembled easily with machining, casting and press working. Of course forming said first passage and second passage with casting or press working is less expensive.
Furthermore, the present invention may provide a humidifier comprised of at least one hollow fiber membrane module formed by inserting into a cylindrical housing, both ends of which are opened, a bunch of water-permeable hollow fiber membrane along the axis of said housing, fixing both ends of said bunch at the outer circumference sides onto both ends of said housing at the inner circumference sides by means of a resin to thereby block the ends of said housing so as to form a plurality of peripheral apertures which are communicated within said housing at several intervals in the circumferential direction, a first passage which allows gas for flowing from one end of said peripheral apertures to the other end thereof serving as an inlet and an outlet, and a second passage which allows gas for flowing from one end to the other of the bunch of said hollow fiber membrane, and what is more, in aforementioned, said first passage and said second passage being sectioned by a plurality of overlapped plates having indentation portions.
That is to say, when said first passage and second passage are sectioned by denting a contact surface of a plurality of plate polymerized each other, these two passage can be formed under the condition to have made open the first passage and the second passage out.
This allows the first passage and the second passage to be formed and assembled easily with machining, casting and press working. Of course forming said first passage and second passage with casting or press working is less expensive.
What is more, the present invention provides a humidifier wherein a lower portion of said first passage for allowing the gas for flowing towards respective peripheral apertures formed on one end of said housing is formed in a chamber state which surrounds the respective peripheral apertures along with the circumferential direction in such a manner that the flowing rate become the same at all cross-sections of said first passage from the upstream to the downstream, and an upper portion of said first passage for allowing the gas for flowing towards respective peripheral apparatuses formed on one end of said housing is formed in a chamber state which surrounds the respective peripheral apertures along with the circumferential direction in such a manner that the flowing rate become the same at all cross-sections of said first passage from the upstream to the downstream.
That is to say, in order to discharge a gas penetrating into inside of the housing via each peripheral aperture formed in one end of the housing from each peripheral aperture formed in the other end of the housing, it is assumed that the down stream of the first passage to inflow gas into a plurality of peripheral aperture of one end of housing is concentrically formed for a plurality of peripheral aperture, meanwhile, the up stream of first passage to inflow a gas from a plurality of peripheral aperture of the other side of housing is concentrically formed for peripheral aperture of other portion of this housing.
However, since a gas streaming around a plurality of peripheral aperture of one end of housing is sequentially coming into a peripheral aperture of down stream from that of up stream, flow velocity of gas streaming around each peripheral aperture and a pressure distribution around each peripheral aperture of one end of housing is varied, consequently, inlet pressure of peripheral aperture of the down stream is decreased compared with inlet pressure of that of up stream. What is more, since outlet pressure for a plurality of peripheral aperture of other end of housing is also proportional to inlet pressure, inflow of gas in housing is disproportionate. Accordingly, in related structure, inlet and outlet flow rate of gas for the housing is decreased, and moisture exchanging for a plurality of hollow fiber membrane in housing is disproportionate, an improvement in moisture exchanging rate of whole equipment can not be expected.
Therefore, the present invention materializes the equalization of inlet pressure for each peripheral aperture of one end of the housing as equalization of flow velocity (inflow velocity) of the down stream of the first passage for a plurality of peripheral apertures of one end of said housing, specifically, as invariable inlet velocity for each peripheral aperture by comprising said downstream so that velocity is uniformed even in every route section from the upstream to the downstream for each peripheral aperture of the downstream portion of this first passage, in the meantime, for each peripheral aperture formed on one edge of said housing, forming the downstream portion of said first passage to inflow gas as chamber shape radially surrounding each peripheral aperture.
Furthermore, the outlet pressure of each peripheral aperture of one end of the housing is equalized to allow gas to uniformly stream in the housing by forming the up stream portion of chamber of said first passage to discharge gas for each peripheral apertures of the other end of said housing so that flow velocity is uniformed even in every route section from the up stream to the down stream for each peripheral apertures.
This allows moisture to be equally exchanged for a planarity of hollow fiber membrane stored in the housing to improve a moisture-exchanging rate in the whole of equipment.